In recent years, a high-capacity optical disc called Blu-ray disc (BD, registered trademark) is commercialized.
This high-capacity optical disc attains about 25 GB recording capacity with about 405 nm of light wavelength for recording and reproduction and about 0.85 of a numerical aperture (NA) of a collective lens as an optical system for recording and reproduction.
In this high-capacity optical disc, in order to attain a recordable optical disc, various types of recordable recording layer materials are considered.
As a recording layer material for a recordable optical disc in related art, an organic dye material has been known.
However, if an organic dye material is used, there is a problem that sufficient productivity cannot be obtained and a problem of long-term stability and storage properties for a recording signal.
Further, there is also a problem that an appropriate organic dye that can be used for light for recording and reproduction with about 405 nm of wavelength is not found.
In this regard, it is considered to use an inorganic material as a recordable recording layer material.
For example, an optical recording medium having a recording layer that contains Te—O, which is crystallized rapidly with rising temperature and causes an optical change, or the like, is proposed (see Patent Document 1).    Patent Document 1: Japanese Patent Application Laid-open No. 2008-112556